Complementary approaches with and without a Fourier plane for optical image processing education

Abstract

We present two laboratory experiments on optical image processing which show complementary modeling approaches. One experiment is based on an optical correlator, where a physical Fourier plane can be identified, and the other is based on the angular response exhibited by a volume grating (Bragg processing) where no Fourier plane is available. In the correlator the frequency content can be visualized as intensity variations in the Fourier plane, whereas in Bragg processing the angular plane waves decomposition of the object is the intuitive approach. Then we have two different approaches to synthesize the transfer function of the system. The combination of the two experiments in a student's lab helps for a deeper understanding of optical image processing, its linear systems mathematical background, and some aspects of volume holography.